# Tag Info

Accepted

### Extending NDSolve beyond a singularity

We can treat the variable $y$ as an element $[y_1 \colon y_2]$ of the projective line. In code, this means replacing y[x] by ...
• 217k
Accepted

### NIntegrate: the order of singular points matters!

Note that {x, x1, x2, x3,..., xn} describes a path in the real or complex domain, and the order matters. So {x, -5, 2, 0, 5}] ...
• 217k

### What can one do with extremely stiff problem in NDSolve?

EDIT #2 My error was useful. It brought me to the conclusion that the difficulties in solving the PDE of the OP are due to the drift term $$\frac{\partial (x u(x,t))}{\partial x}$$ If the drift ...
• 12.8k

• 2,443
Accepted

### How to evade singularity or stiff system suspected in NDsolve?

Some progress can be made as follows. First, as noted in my comment above, evaluating Ba at the initial conditions in the question yields ...
• 58.4k

### How to solve second order nonlinear differential equation?

The desired solution can be obtained semi-analytically. ...
• 58.4k